Rotary engine.



No. 718,791; PATENTED JAN. 20, 1903; J. B. POLLARD.

ROTARY ENGINE.

APPLICATION FILED APB.14, 1902.

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NTTED STATES PATENT @FFICE.

JAMES BAKER POLLARD, OF ROANOKE, VIRGINIA.

ROTARY ENGINE.

SPECIFICATION forming part of Letters Patent No. 718,791, dated January20, 1903.

Application filed April 14,1902. Serial No. 102.880. (N0 model.)

To all, whom, it may concern.-

Be it known that I, JAMES BAKER POLLARD, a citizen of the United States,and a resident of Roanoke, in the county of Roanoke and State ofVirginia, have made a certain new and useful Invention in RotaryEngines; and I declare the following to be a full, clear, and exactdescription of the same, such as will enable others skilled in the artto which it appertains to make and use the invention, reference beinghad to the accompanying drawings, and to letters of reference markedthereon, which form a part of this specification.

Figure 1 is a side elevation of my engine. Fig. 2 is a section ontheline 2 2, Fig. 3. Fig. 3 is a section on the line 3 3, Fig. 1. Figs.4and 5 are detail views illustrating the connection of lever M with rodK.

This invention has relation to rotary engines, and is designed toprovide an engine of this class which is simple and practical in itsconstruction and operation and which is economical in point of steamconsumption.

With these objects in view the invention consists in the novelconstruction and combination of parts, all as hereinafterdescribed, andpointed out in the appended claims.

Referring to the accompanying drawings, the letter A designates the openbed of the engine, to which is secured an engine-casing B. This casingconsists of a cylindrical body portion and two endheads B B, into whichthe ends of the body portion are shouldered, as shown at b.

O designates the engine-shaft, which hasa bearing at c in a boss oraxial extension of the casing-head B. r

The casing B is divided into two compartments or chambers by a verticalpartition D, and in each of said compartments is a powerwheel or rotarypiston E or E, which fits neatly therein, but so as to turn withoutfriction. The wheel E is rigidly connected to the inner end of the shaft0, while the wheel E is secured on a hollow sleeve-shaft F, to which thewheel E is also secured. Each of the said wheels has therein ascroll-shaped or volute spiral steam-passage G, which extends from thecenter of the wheel out through the periphery thereof, as shown. Thesesteam-passages are the same in the two wheels, except that they extendin opposite directions to each other, as indicated in Fig. 2.

The hollow sleeve-shaft F, above referred to, has a bearing at its outeror right-hand end portion in an extension 19 of the casinghead B, and itextends axially through the wheel E, the central partition D, and intothe inner end portion of the passage G of the wheel E. It is closed atits inner end, is open at its outer end, and has two portsf, whichcommunicate with the passage of the wheel E, and two ports f, whichcommunicate with the passageof the wheel E. Fitted to reciprocate withinthe said shaft is a cylindervalve H, which has ports h, which aredesigned to be brought to register with the ports h, and other ports 72,which are designed to be brought to register with the ports f. Thisvalve has a closed inner end, but is open at its outer end.

The extension I) of the head B", above referred to, has formed thereinan internallythreaded seat or chamber for a steam cylinder or chest I,to which steam is admitted by a supply-pipe I and which communicateswith the open end of the sleeve-shaft F by means of a passage J.

Connected to the open end of the valve H is a rod K, which extendsthrough the shaft F, the passage J, and the steam-chest I, the latterhaving in its outer head a stufifing-box L for the said rod. M is alever for operating the said rod and thereby the valve to control theadmission of steam to either one or neither of the two power-wheels.This lever is pivoted at its lower end to one end of a link L, which inturn is pivoted to a fixed support L. The lever M engages the rod Kbetween two collars k thereof and has a loose sleeve m set on thepivot-studs m.

N designates packing-rings which are provided at the points of bearingof the shafts O and F, as shown. The valve H has a packing-ring N.

It will be understood from the foregoing and from the drawings that bothwheels E E revolve together and that the shaft F and valve H alsorevolve therewith, the direction of rotation being determined accordingto which of the wheels steam is admitted.

P P designate two exhaust-pipes which entirely surround the casing B,one around each compartment thereof, and which commu nicate with theirrespective compartments by means of a series of short pipes P. The pipesP are each provided at the top of the engine or at some other convenientpoint with an escape or return pipe R and a shut-oil: or regulatingvalve R, and at the bottom each of said pipes P has a drain-pipe S forcarrying off the water of condensation and a cut-off or drain valve S.

Steam being admitted to the wheel E orE' at the center thereof passesout through the passage G and against the inner wall of thecasing-compartment, thereby by its reactionary force causing therotation of said wheel in a direction reverse to the direction of thesaid passage. By means of the valves R and S the steam can be held inthe wheels until it condenses or until its energy is lost, therebyutilizing to a maximum degree the energy of the steam and making theengine an economical one in point of steam consumption.

I desire to state that while in describing the engine I have referred tosteam as the motive power compressed air may be used as the motivepower, the engine being adapted to the use of either steam or air.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is

1. In a rotary engine, the combination with an inclosed chamber, of arotary piston, or power-wheel journaled therein to turnin close relationto the wall of said chamber but Without friction thereon, said wheelhaving therein a continuous spiral or scroll-shaped steampassageextending from its central portion out through its circumference, meansfor supplying steam to the said passage at its inner end portion, and avalved exhaust-pipe, substantially as specified.

2. In arotary engine, the combination with a closed chamber,of a rotarypiston or powerwheel journaled therein, and containing a spiral orscroll-shaped steam-passage which extends from its central portion outthrough its periphery, means for supplying steam to the inner endportion of the said passage, an exhaust-pipe surrounding the saidchamber exteriorly thereof, and communicating therewith byconnecting-pipes at different points around its circumference and valvedescape and drain pipes connected to the said exhaust-pipe, substantiallyas specified.

3. In a rotary engine, the combination with a casing divided into twocompartments, of a power-wheel, or rotary piston in each of the saidcompartments and connected with each other to rotate together, each ofthe said wheels having therein a spiral or scroll-shaped steam-passagewhich extends continuously from its central portion to and through itscircumference, the said passages in the two Wheels extending in oppositedirections, the steam-chest at one end of the said casing, the hollowshaft which extends centrally through one of the said wheels, and intothe central portion of the other, and which has ports which communicatewith the inner ends of the steam-passages of both wheels, said shafthaving communication with the steam-chest, areciprocating valve in thesaid shaft for controlling its said ports, means for operating the saidvalve, and exhaust-pipes which communicate with the said compartments,substantially as specified.

4:. In a rotary steam-engine, the combination with the casing dividedinto two compartments,of the power-wheels, or rotary pistons, one ineach of said compartments, and having each therein a continuous spiralor scroll-shaped steam-passage which extends from its central portion toand through its circumference, said passages extending in oppositedirections in the two wheels, the central hollow shaft which connectsthe two wheels, and which has ports opening into the steampassagethereof, a steam-chest with which the said shaft communicates at oneend, a reciprocating hollow cylinder-valve in said shaft for controllingthe ports thereof, means for operating the said valve, and anexhaust-pipe surrounding each of the said chambers or compartments,exteriorly thereof, and communicating therewith at di1ferent pointsaround their circumferences, substantially as specified.

In testimony whereof I afiix my signature in presence of two witnesses.

JAMES BAKER POLLARD.

Witnesses:

H. M. DARNALL, A. S. ASBURG.

